Towards a sweat-based wireless and wearable electrochemical sensor

The analysis of biomarkers within sweat is advantageous for both being a non-invasive diagnostic method as well as the physiological relevance of the present biomarkers. Due to these advantages, having a wearable system that can continually perform sweat analytics holds potential for various applications. In order to create a wearable system that operates efficiently, both the electrochemical sensor and the front-end electronic system need to be optimized. In this paper, we present our work on the electronic interface portion for use with skin adhered biosensors. For proof of concept, we focused on the sensing of lactate; the conjugate base of lactic acid. Our system was shown to calibrate itself using cyclic voltammetry and measure concentrations of lactate from 0.1 mM to 0.75 mM. The system can wirelessly transmit readings to a peripheral smart-phone data aggregator, and continuously operate for over 36 hours.